Observations were made of the reconstruction of a Si(111)-(√3 x √3)-Sb surface phase, induced by atomic H, using scanning tunnelling microscopy and time-of-flight elastic recoil detection analysis. When a Si(111)-√3 x √3-Sb surface was exposed to H at room temperature, depending on H amount, the surface structure was transformed into a 2 x 1 phase. The surface reaction started at the original domain boundaries and surface defects. In such a process, most Sb atoms were not replaced by hydrogen atoms, so no agglomeration of Sb atoms was observed. The hydrogen coverage of the reacted surface was as low as 0.1 to 0.2 monolayers, and about one-half of the H appeared to form bonds with Sb atoms. These results were quite different to the metal island formation induced by H on other metal/Si(111) surfaces. Sb Atom Reconstruction Induced by Atomic Hydrogen Interaction with Si(111)-√3 x √3-Sb Surface. O.Kubo, T.Fujino, J.T.Ryu, K.Oura, M.Katayama: Surface Science, 2005, 581[1], 17-23